ABSTRACT
Objective To explore the changes of whole brain white matter ( WM) structural net-work topological property in patients with schizophrenia (SP) and the associations between WM networks to-pological efficiency and clinical variables in patients. Methods Deterministic tractography was used to con-struct the WM networks of 59 patients with SP ( patients group) and 41 age-, handedness-, and gender-matched healthy controls (HCs),and graph theoretical methods were applied to investigate abnormalities in the global and nodal properties of the WM network in these patients. Partial correlation analysis was used to analyze the relationship between global and nodal properties of the WM network and clinical variables in pa-tients with SP. Results Both the patients with SP and HCs showed small-world organization of the WM net-works. However,compared with HCs,the patients with SP exhibited significant abnormal global topology,in-cluding increased shortest path length ( t=7. 95, P=0. 0001) and decreased global efficiency ( 30. 83 ± 16. 08,8. 25±6. 13,t=-9. 81,P=0. 002),clustering coefficiency (0. 03±0. 01,0. 02±0. 01,t=-4. 48,P=0. 0003),the average clustering coefficiency (t=-8. 28,P=0. 002),the small-worldness (3. 92±0. 79,2. 79 ±0. 56,t=-7. 82,P=0. 001) of their WM structural networks(all P<0. 005,FDR corrected). Further,the patients with SP showed a reduction in nodal efficiency predominately in the cingulate gyrus ( t=-4. 11, P=0. 000),superior occipital gyrus ( t=-6. 05, P=0. 002), superior temporal gyrus ( t=-10. 46, P=0. 001),middle temporal gyrus (t=-10. 38,P=0. 000),thalamus (t=-6. 10,P=0. 000) and putamen ( t=-8. 38,P=0. 000) (P<0. 005,FDR corrected). Partial correlation results showed that there was no signifi-cant correlation between global topological properties,node efficiency and clinical symptoms in patients group (Eglob:r=-0. 14,P=0. 279;Eloc:r=-0. 06,P=0. 628;Lp:r=0. 28,P=0. 031;Cp:r=0. 27,P=0. 043;λ:r=-0. 18,P=0. 166;γ:r=-0. 29,P=0. 026;σ:r=0. 26,P=0. 048;nEglob:r=0. 36,P=0. 005;nEloc:r=0. 02,P=0. 901). Conclusions The patients with SP exhibit the abnormal of whole brain WM structural network topological property and the node efficiencies of cortico-striato-thalamo circuitry are significantly re-duced.
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Objective To analyze the topological characteristics of the brain structural network in primary angle-closure glaucoma (PACG) patients by applying graph theoretical approaches.Methods From October 2015 to April 2017, nineteen PACG patients and nineteen gender-and age-matched healthy controls (HCs) were enrolled to undergo MRI scan. The whole brain was parceled into 90 regions by automated anatomical labeling template, and the brain structural network was constructed by the fiber distribution of continuous tracking method.Both the weighted and unweighted network analyses were performed.The global and regional properties were computed by graph theoretical analysis.To compare the brain network regional properties between two groups, two-sample t-test was utilized.The correlations between the brain structural network properties and clinical parameters were further analysed. Results Both two groups were found to follow the efficient small-world characteristics. Compared to HCs, the brain structural network in PACG patients showed no statistical significance in the small-worldness, average shortest path, clustering coefficient, global efficiency and local efficiency(P＞0.05). Compared to the HCs, the PACG patients showed decreased nodal efficiency in the right superior frontal gyrus, right inferior frontal gyrus, left median cingulate and paracingulate gyri, left amygdala and left cuneus(P＜0.05). Compared to HCs, the PACG patients showed decreased node degree in left superior frontal gyrus, medial orbital, right inferior frontal gyrus, left amygdala, left cuneus and left lingual gyrus(P＜0.05). Compared with the hub regions in healthy controls'network, we found that two hub regions disappeared.Those hubs were right inferior parietal lobule and left middle temporal gyrus. Node degree in left amygdala showed negatively correlated with visual ability (r=-0.679, P=0.001). Node degree in left lingual gyrus showed negatively correlated with vertical CDR(r=-0.791, P=0.001),which showed positively correlated with visual acuity(r=0.538, P=0.018).Conclusions The brain structural network in PACG patients showed small-worldness properties as HCs group. The alterations of local properties in visual, emotion-cognition brain regions were observed, manifesting that PACG can affect the topology properties of the structural brain network.
ABSTRACT
The technology of network analysis, based on a variety of disciplines theory, is the core technology in the research of network pharmacology, through which we can mine specified information from molecular networks from multi-angle and multi-level. It has been used to investigate and obtain valuable information about the ingredients/drugs with specific pharmacological effects, the key nodes, modules and motifs with specific biological function, and physiological mechanism of drug action, pathogenesis of disease, or biomarker of disease, especially for the complex disease represented by Alzheimer’s disease (AD). In this paper, the general techniques of network analysis in network pharmacology study are reviewed.
ABSTRACT
The technology of network analysis,based on a variety of disciplines theory,is the core technology in the research of network pharmacology,through which we can mine specified information from molecular networks from multi-angle and multi-level. It has been used to investigate and obtain valuable information about the ingredients/drugs with specific pharmacological effects ,the key nodes,modules and motifs with specific biological function,and physiological mechanism of drug action,pathogenesis of dis?ease,or biomarker of disease,especially for the complex disease represented by Alzheimer′s disease(AD). In this paper,the general techniques of network analysis in network pharmacology study are reviewed.
ABSTRACT
Objective To explore the differences of the connectivity strength,the clustering coefficient and the local efficiency of the nodes in the brain structural networks in the depression and healthy subjects and then analyze the mode of the local connections of the brain regions and their local efficiency of the transmission of information and their relationship with the severity of the disease in the depression.Methods The Diffusion Tensor Imaging data were obtained from 24 depression patients and 25 healthy controls.The whole cerebral cortex was parcellated into 90 regions by the anatomical label map.Tractography was performed in the whole cerebral cortex of each subject to reconstruct white matter tracts of the brain using the fiber assignment by continuous tracking (FACT) algorithm.And then the brain structural networks were constructed using the complex network theory.The local topological properties of the brain structural networks of the depression and healthy were examined by two sample t-test.Results The local efficiency of the nodes of the networks in depression decreased significantly (the left middle frontal gyrus (orbital part):0.64±0.30,the left hippocampus:0.57±0.07,the right parahippocampal gyrus:0.50±0.15) compared with the healthy (0.88±0.10,0.64±0.06,0.66±0.13 respectively,P=0.00098,0.00039,0.00017,survived critical FDR threshold for multiple comparisons) ; and the clustering coefficient of the nodes of the networks in depression (the left middle frontal gyrus (orbital part):0.14±0.07) decreased significantly when compared with the healthy (0.22±0.06,P=0.000030,survived critical FDR threshold for multiple comparisons).Significant negative correlation was found between the local efficiency of the left middle frontal gyrus (orbital part) and the total scores of HAMD-17 in the depression (r=-0.48,P=0.02).Conclusion The degree of the localization and the local efficiency of the information transmission of the frontal lobe are decreased.The local efficiency in the information transmission in the hippocampal is also decreased.And the local efficiency of the frontal lobe is negatively related with the severity of the disease in the depression.